The Kekule structure of benzene failed to explain

  • A. the molecular formula C6H6
  • B. the ring shape of the molecule
  • C. why benzene resists addition reactions and has all its carbon to carbon bonds of equal length
  • D. why benzene contains only carbon and hydrogen

Explanation

Alternating single and double bonds would predict two different bond lengths and the ready addition reactions of an alkene, but experiment shows a single intermediate bond length of 0.139 nm and a strong preference for substitution. The modern picture replaces the alternating bonds with a delocalised ring of six pi electrons above and below the plane. That delocalisation is what makes benzene unusually stable.

Related questions